Optoelectronic component with a conductor strip element

ABSTRACT

A further miniaturization of known optoelectronic components with internal screening is not possible. In addition, inhomogeneities occur in the embedding material. Separate screening plates cause additional costs to arise during component assembly. The task is to design an optoelectronic component with a conductor strip element such that screening can be effected without any additional external screening measures.  
     Optoelectronic component with a conductor strip element, with electronic and optoelectronic semiconductor components being arranged on a first conductor strip element area connected to ground and encapsulated by a housing made of thermo or duroplastic synthetic material. A second conductor strip element area protrudes from the housing and is folded around the housing such that it screens the semiconductor components against electromagnetic interference radiation.  
     The invention is particularly suitable for opto-electronic components such as, for example, photo modules that are to be mounted in top-view position as well as in side-view position and which contain electronic or optoelectronic semiconductor components that need to be protected against electromagnetic interference radiation.

BACKGROUND OF THE INVENTION

[0001] The invention relates to an optoelectronic component with aconductor strip element in accordance with the preamble of patent claim1 and a procedure for manufacture according to the preamble of patentclaim 15.

[0002] Such a state of the art optoelectronic component with a conductorstrip element is known, for example, from the European patentpublication EP 0 566 921 A1. For electromagnetic screening within itshousing, this component features a folded-over strip elementencapsulated by embedding compound. However, a minimum thickness of theembedding material above the screening is necessary. For this reason anddue to the internal arrangement of this component, furtherminiaturization is not possible. A further disadvantage is thatinhomogeneities occur in the embedding material between thesemiconductor components and the screening.

[0003] From the Patent Abstract of Japan No. 11154758 A, it is knownthat, for electromagnetic screening, the housing of an optical receiverunit for infrared control signals—consisting of synthetic resin—needs tobe coated with nickel. The coating of the synthetic resin housing with anickel layer represents a very costly and work-intensive process. Anadditional difficulty is presented by the zone which must not be coatedwith nickel in order to remain transparent for infrared radiation.Furthermore, it is difficult to connect the nickel layer to ground.

[0004] In addition, for electromagnetic screening, separate metal partsare known, e.g. from the documents EP 0 524 406 A1 or U.S. Pat. No.5,432,340, that are manufactured as separate screening plates or hoodsand arranged around the component areas to be protected. Thedisadvantage of such separate screening plates is that additional costsarise during component assembly.

SUMMARY OF THE INVENTION

[0005] The object of the invention is to provide for the design of anoptoelectronic component with a conductor strip element such that ascreening of its parts to be protected against electromagneticinterference radiation can be effected without any additional externalscreening measures.

[0006] According to the invention there is an optoelectronic componentwith a conductor strip element, with electronic and optoelectronicsemiconductor components being arranged on a first conductor stripelement area connected to ground and encapsulated by a housing made ofthermo- or duroplastic synthetic material, wherein a second conductorstrip element area—also connected to ground—protrudes from the housingand is folded around the housing such that it will screen thesemiconductor components against electromagnetic interference radiationand a procedure for the manufacture of an optoelectronic component, withthe following process steps:

[0007] Provision of a conductor strip element connected to ground, witha first conductor strip element area,

[0008] Mounting and contacting electronic and optoelectronicsemiconductor components on the first conductor strip element area,

[0009] Manufacture of a housing around the first conductor strip elementarea and the semiconductor components by molding with a thermo- orduroplastic material,

[0010] wherein

[0011] a second conductor strip element area is folded around thehousing as an electromagnetic screen.

[0012] The invention has the advantages that, when compared with theexisting components, much more compact housing formats can beimplemented, also as top-view-side-view combinations (top-view: opticalaxis runs vertical to the mounting plane, side-view: optical axis runsin parallel to the mounting plane). Due to the design and constructionselected, the galvanic connection of the screening element to groundwill remain intact nevertheless.

[0013] The invention is particularly suitable for opto-electroniccomponents such as, for example, photo modules that are to be mounted intop-view position as well as in side-view position and which containelectronic or optoelectronic semiconductor components that need to beprotected against electromagnetic interference radiation.

[0014] Advantageous further embodiments of the object according to claim1 and the process according to claim 15 are stated in the sub-claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In the following the invention will be explained by means of anembodiment example and the drawing. The figures below show:

[0016]FIG. 1: a two-part conductor strip element populated withelectronic and optoelectronic semiconductor components,

[0017]FIG. 2: the conductor strip element from FIG. 1, whose firstconductor strip element area with the semiconductor components isencapsulated by embedding material, and

[0018]FIGS. 3a, b: two perspective views of a ready-mountedoptoelectronic component with a bent-over second conductor strip elementarea for screening.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019]FIG. 1 shows a section from a conductor strip element 1 with aframe 1′ with the conductor strip element 1 being manufactured, usingthe known process, by punching or etching from a thin longitudinal stripof sheet metal, and features longitudinal positioning apertures 2, roundtransportation apertures 3, and connection pins 8. Furthermore theconductor strip element 1 comprises a first conductor strip element area4 and a second conductor strip element area 5, with the first conductorstrip element area 4 being populated with an optoelectronicsemiconductor component 6, for example a receiver for infraredradiation, as well as with an electronic semiconductor component 7, forexample, an integrated circuit. The first conductor strip element area 4can be populated with further optoelectronic and electronicsemiconductor components.

[0020] The connection pins 8 are later bent-over twice and bent into aspecific form and are preliminarily used to connect the first conductorstrip element area 4 with the frame 1′. One of the connection pins 8,which is later connected to ground, forms a component part of theconductor strip element 1, so that both conductor strip element areas 4and 5 are connected to ground. The semiconductor components 6, 7 arecontacted with one another, or with the conductor strip element 1 in theknown manner.

[0021] The second conductor strip element area 5 is connected to thefirst conductor strip element area 4 by means of one or several lands 9,and features a first aperture 10, a second aperture 11, two notches orcuts 12 and a further land 13 connected to the frame of the conductorstrip element 1. Although the land 13 only serves to connect the secondconductor strip element area 5 to the frame 1′, and is later separatedfrom the conductor strip element area 5, it can also remain connected tothe conductor strip element area 5 as a part of the screening (and isthen separated from frame 1′). Instead of the two lands 9 for connectingthe two conductor strip element areas 4 and 5, it is also possible touse a single wider land 9. Two wings 19 follow the two notches or cuts12 and, when the conductor strip element 1 is manufactured, are angledoff by a small angle along a respective bending line 20 (the purpose ofthis will be explained below).

[0022] The first aperture 10 advantageously features a circular formwith a specific diameter and is located approximately at the center ofthe conductor strip element area 5; the second aperture 11 preferablyfeatures a longitudinal form with a longitudinal axis 14. Thelongitudinal axis 14 also represents a bending line, along which at alater point in time a part section 16 of the second conductor stripelement area 5 is bent over at an approximate right angle. The twonotches or cuts 12 run along a line 15, which in turn runs in parallelto the bending line or longitudinal axis 14 of aperture 11.

[0023]FIG. 2 shows the conductor strip element I with the unchangedconductor strip element area 5. In order to produce a housing 21, thefirst conductor strip element area 4, with the semiconductor components6, 7 (FIG. 1) mounted on the same, is encapsulated by means of a moldingprocess with a thermo- or duroplastic synthetic material transparent toinfrared radiation, e.g. a synthetic resin suitable for injectionmolding.

[0024] A round flattened lens 17 for focusing the infrared radiation isintegrated in housing 21 . The form and diameter of lens 17 and the formand diameter of aperture 10 in the second conductor strip element area 5are matched so that lens 17 fits through the aperture 10 . Furthermore,housing 21 features a recess 18 which is dimensioned such that the partsection 16, which is to be bent over, from the second conductor stripelement area 5, fits into this recess 18 .

[0025] If the land 13, for screening, remains connected to the secondconductor strip element area 5, then the housing 21 can advantageouslyfeature a further recess, which is dimensioned such that it canaccommodate land 13. The lens 17 is flattened and thus obtains a gripsurface 27, to allow the suction needle of an automatic assembly machineto dock onto this grip surface 27.

[0026]FIGS. 3a and 3 b, respectively, show a perspective view of aready-mounted optoelectronic component 23 which may be, for example, aphoto module fitted into audio or video systems which photo modulereceives by means of infrared radiation the control commands from aremote control unit and passes them on as electrical signals.

[0027] The connection pins 8 are bent over twice so that the component23 can be assembled onto a printed circuit board in top-view position orin side-view position. The lands 9 are also bent over twice, and thesecond conductor strip element area 5, as a screening againstelectromagnetic interference radiation, is thus folded over housing 21such that the lens 17 protrudes through the aperture 10 . If the land 13has not been removed, it can be simply angled off as a side screeningshield 28 (drawn in by a dotted line). The side screening shield 28 canalso be designed such that it is longer, angled twice and bent aroundthe housing 21 within a possibly existing recess, so that the screeningsecond conductor strip element area 5 does not spring back.

[0028] Another possibility to prevent the conductor strip element area 5from springing back is to provide an incline 24 within the recess 18 inhousing 21, which incline ends as a sharp-edged step 25. After the part16 of the conductor strip element area 5 is bent along line 14 at anapproximate right angle, the wings 19, angled around a small angle alongthe respective bending line 20, will slide along the incline 24 when thesecond conductor strip element area 5 is folded over; and the wings 19will engage on step 25; this will hold the entire conductor stripelement area 5 in this position, and prevent the same from springingback. This second possibility to prevent the conductor strip elementarea 5 from springing back can alternatively be also applied to thesecond screening shield 28 and the possibly existing associated recessin housing 21.

[0029] The invention shows a simple way in which electronic oroptoelectronic components such as e.g. photo modules can be protectedagainst electromagnetic interference radiation.

What is claimed is:
 1. Optoelectronic component (23) with a conductorstrip element, with electronic and optoelectronic semiconductorcomponents (6, 7) being arranged on a first conductor strip element (4)connected to ground and encapsulated by a housing (21) made of thermo-or duroplastic synthetic material, wherein a second conductor stripelement area (5)—also connected to ground—protrudes from the housing(21) and is folded around the housing (21) such that it will screen thesemiconductor components (6, 7) against electromagnetic interferenceradiation.
 2. Optoelectronic component (23) according to claim 1 whereinthe two conductor strip element areas (4,5) are connected to one anotherby means of one or several lands (9).
 3. Optoelectronic component (23)according to claims 1 or 2 wherein a lens (17) is integrated into thehousing (21).
 4. Optoelectronic component (23) according to one of theclaims 1 to 3 wherein the second conductor strip element area (5)features an aperture (10).
 5. Optoelectronic component (23) according toclaims 3 and 4 wherein the form and diameter of the lens (17) and theform and diameter of the aperture (10) are matched.
 6. Optoelectroniccomponent (23) according to one of the claims 1 to 5 wherein the secondconductor strip element area (5) features a part section (16) to be bentover.
 7. Optoelectronic component (23) according to claim 6 wherein thepart section (16) features two notches or cuts (12).
 8. Optoelectroniccomponent (23) according to claim 7 wherein each notch (12) is followedby a wing (19).
 9. Optoelectronic component (23) according to claim 8wherein each wing (19) is angled off by a small angle. 10.Optoelectronic component (23) according to one of the claims 1 to 9wherein the housing (21) features an incline (24) with a final step(25).
 11. Optoelectronic component (23) according to claims 9 and 10wherein the angled wings (19) are engaged in the step (25) when theconductor strip element area (5) is folded over.
 12. Optoelectroniccomponent (23) according to one of the claims 1 to 11 wherein the secondconductor strip element area (5) features a further land (13). 13.Optoelectronic component (23) according to claim 12 wherein the land(13) is bent around the housing (21) when the conductor strip elementarea (5) is folded over.
 14. Optoelectronic component (23) according toclaims 12 or 13 wherein the housing (21) features a recess for the land(13).
 15. Procedure for the manufacture of an optoelectronic component(23), with the following process steps: Provision-of a conductor stripelement (1) connected to ground, with a first conductor strip elementarea (4), Mounting and contacting electronic and optoelectronicsemiconductor components (6, 7) on the first conductor strip elementarea (4), Manufacture of a housing (21) around the first conductor stripelement area (4) and the semiconductor components (6, 7) by molding witha thermo- or duroplastic material, wherein a second conductor stripelement area (5) is folded around the housing (21) as an electromagneticscreen.